Does " has not grappled with" refer to "has not made efforts to answer"?

Context:

Lewis still has not grappled with the deeper questions for his
readers, He still has not offered his explanation for why the
Islamic Middle East stagnated, why its efforts at reform failed,
why it is notably failing to become integrated into the global
economy in a meaningful way and why these failures have produced
not a renewed determination to succeed (as in East Asia over the past 50 years, and arguably in India, Latin America and
even parts of sub-Saharan Africa today) but an anger and frustration
with the West so pervasive and vitriolic that it has bred
murderous, suicidal terrorism despite all of the Islamic prohibitions
against such action.16